|  | 2.1 | Various LAN Communication Problems
| 2.1.2 | Elements of Ethernet/802.3 networks
The most common LAN architecture is Ethernet. Ethernet is used to transport data between devices on a network, such as computers, printers, and file servers. As shown in the graphic, all the devices are connected to the same delivery medium. Ethernet media uses a data frame broadcast method of transmitting and receiving data to all nodes on the shared media. The performance of a shared-medium Ethernet/802.3 LAN can be negatively affected by several factors: The data frame broadcast delivery nature of Ethernet/802.3 LANs Carrier sense multiple access collision detect (CSMA/CD) access methods allowing only one station to transmit at a time Multimedia applications with higher bandwidth demand such as video and the Internet, coupled with the broadcast nature of Ethernet, can create network congestion. Normal latency as the frames travel across the Layer 1 medium and through Layer 1, 2, and 3 networking devices, and the latency added by the extension of Ethernet/802.3 LANs by adding repeaters Extending the distances of the Ethernet/802.3 LANs by using Layer 1 repeaters Ethernet using CSMA/CD and a shared medium can support data transmission rates of up to 100 Mbps. CSMA/CD is an access method that allows only one station to transmit at a time. The goal of Ethernet is to provide a best-effort delivery service and allow all devices on the shared medium to transmit on an equal basis. As shown in Figure , one of the inherent problems with CSMA/CD technology is collisions.
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